Grey water conservation mechanism

ABSTRACT

A gray water recycling system which uses a holding tank receiving waste water from a laundry facility. The holding tank has a pump for withdrawing water from said holding tank. A float, within said holding tank, is activated when a water level within said holding tank exceeds a pre-determined level. The pump communicates with a pressure tank. The pump used to fill and pressurize the pressure tank is activated when pressure within said pressure tank falls below a predetermined level and the float within said holding tank indicates that a water level within said holding tank exceeds a pre-determined level.

BACKGROUND OF THE INVENTION

This invention relates to conservation in general and more particularly to conservation of water.

The demand for water is increasing and the general fresh water supply is not. Growth in agriculture, industry, household, and recreational uses have placed significant strains on the already limited fresh water supply

Add to this the affects of pollution and the actual supply of available usable fresh water is dwindling while the world's population continues to grow.

Supplying this growing population has required a huge expenditure in infrastructure, pumping stations, and water treatment works. At the present time, estimates are that four out of every ten people live without improved sanitation and only about half of the world's population has a piped water supply to their home.

To expand the usefulness of this limited water supply, one approach has been to re-use water a second time. This is often referred to as grey water or sullage. Grey water is non-industrial wastewater generated from domestic (and sometime industrial) uses such as dish washing, laundry and bathing. Grey water comprises 50-80% of residential wastewater and includes all water from a residence except that from toilets.

Grey water is typically treated through the sewer system by the water treatment plants. Obviously, if grey water were used in a secondary manner, then the load upon the treatment plants would be reduced to only 20-50% of its current load, thereby reducing the costs for this part of the infrastructure.

Use of the gray water include such simple solutions as diverting the water to a garden for a residential application. Unfortunately, in an industrial setting such as motels and hotels, and resorts pumping the grey water to a “garden” is not feasible, but to their landscaping, ponds, and/or golf course is.

It is clear there is a need for an efficient and cost effective mechanism to conserve water by reusing as much as possible.

SUMMARY OF THE INVENTION

The invention is a gray water recycling system which uses a holding tank receiving waste water from a laundry facility. This invention is ideally suited for use in collecting and recycling the gray water from a laundry facility at a hotel or resort. Laundry water, when proper detergents are used, is easily recycled.

Also, since the invention's ideal application is from the laundry system, the invention is easily installed into existing facilities, thus eliminating the need to engineer the system into a building during the planning stage.

In the preferred embodiment, water from the laundry is deposited into a holding tank. The holding tank has a pump for drawing water from said holding tank, and, a float within said holding tank. The float senses the level of the water within the tank; thereby assuring that the tank is not run “dry” which may damage pumps and other mechanisms which are not designed to operate without a water float.

In this manner, the float is activated when a water level within said holding tank exceeds a pre-determined level. A minimal amount of water must exist within the holding tank for the system to operate.

The holding tank communicates with a pressure tank which contains an activation sensor. While the water within the holding tank is not under pressure, the pressure tank is used to assure that proper pressure is maintained for subsequent mechanisms, such as irrigation systems.

A pump draws water from the holding tank and provides this water, under pressure to the pressure tank. The pump filling and pressurizing the pressure tank is activated when pressure within said pressure tank falls below a predetermined level and the float within said holding tank indicates that a water level within said holding tank exceeds a pre-determined level. In this way, the pump is never activated unless there is both sufficient water within the holding tank and there is a need to bring the pressure within the pressure tank up to the desired range.

In the preferred embodiment, the system is based on a standard 100 room hotel. Typically the laundry water consumption of a hotel is in the range of 2500-5000 gallons per day (i.e. 70 loads a day at 60 gallons per load, yields 4200 gallons per day).

A valve at the laundry trough diverts the waste laundry water into a three inch line to a 1000 gallon holding tank which uses effluent filters to eliminate the suspended particles. While those of ordinary skill in the art recognize a variety of effluent filters, the preferred effluent filter is a PL-625 Effluent Filter from Polylok Inc. This filter is able to operate for an extended period before requiring any maintenance such as cleaning or replacement and has been found to remove fats, oils, and grease by as much as 60-98%.

Alternative filtration system utilize removable cartridges, thereby allowing the user to periodically replace or clean the cartridge.

The now filtered waste water is communicated to an underground 2500 gallon holding tank with an effluent pump and floats. The preferred effluent pump is commercially available from Ofrenco Systems Inc., commercially known as the P Series Effluent Pump.

The underground holding tank has an overflow drain communicating with the sewer. This prevents a malfunction in the system causing a leakage from the holding tank. In the preferred embodiment of the invention, a sensor is placed in the overflow drain so that should a malfunction occur, an operator is alerted.

The effluent pump communicates the filtered gray water to a 500 gallon pressure tank which is above ground. A controller senses the pressure within the pressure tank and the presence of gray water from the float within the holding tanks. The controller activates a pump to maintain the pressure within the pressure tank within a desired range of pressure if: (1) there is sufficient water within the holding tank; and, (2) the pressure within the pressure tank is not within the desired range.

The outlet of the pressure tank communicates with a time controlled irrigation box and valves to the hotel's irrigation system. In this manner, pressurized water is communicated to the existing irrigation system.

This water is useful for subsurface irrigation although surface irrigation is a simpler and preferred method of delivering water to the plants. Ideally, in the case of surface irrigation, a disinfectant is used. While those of ordinary skill in the art recognize a variety of disinfectants, some examples of disinfectants are:

a) Chlorination (gaseous chlorine, solid chlorine, and liquid chlorine);

b) Ozone; and

c) Ultraviolet light.

In the preferred embodiment of the invention, the holding tank, the pump, controller, and pressure tank is contained within a single housing, thereby allowing the system to be easily installed. This embodiment is particularly useful for retrofitting residential applications.

With the above invention, not only has the affect of providing irrigation for the hotel, but also reduces the load which must be handled by water district.

The invention, together with various embodiments thereof, will be more fully explained by the accompanying drawings and the following descriptions thereof.

DRAWINGS IN BRIEF

FIG. 1 is a block diagram illustrating the operation of the gray water treatment system.

FIG. 2 is a block diagram illustrating the preferred residential embodiment of the gray water treatment system.

FIG. 3 is a block diagram illustrating the gray water treatment system implemented in a hotel setting.

DRAWINGS IN DETAIL

FIG. 1 is a block diagram illustrating the operation of the gray water treatment system.

Gray water from laundry 10 is communicated via pipe 13F to diverter valve 11A. Diverter valve 11A is used to connect/disconnect the gray water with the system by either directing the gray water flow to pipe 13D (connecting the gray water to the treatment system) or directing the gray water flow to pipe 13E (thereby flushing the gray water into the sewer 19).

The gray water flows through pipe 13D to the filter tank 12 which removes the suspended particles from the gray water and then communicates the now filtered gray water via pipe 13A to holding tank 14. Float 15 within holding tank 14, determines if the gray water within holding tank 14 exceeds a minimal level.

An overflow 9 communicates with holding tank 14 and directs any excess water to the sewer 19. This prevents the system from becoming overwhelmed by the incoming gray water.

Pump 16 draws the gray water from holding tank 14 via pipe 13B and pressurizes pressure tank 17. Pump 16 is activated when there is at least minimal water within holding tank 14 (as defined by float 15) and the pressure within pressure tank 17 is not within a prescribed range.

The pressurized gray water is communicated via pipe 13C to the irrigation box 18 which is equipped with a time to properly dispense the irrigation to the plants. Shut off valve 11B allows the irrigation system to dispense water either to the plants 8 or to be flushed to the sewer 19 via pipe 13E or pipe to an expanded future distribution area 5. In some situation, the gray water needs to be treated. In those situations, an injection line 7 is used for the placement of chlorine or such into the tank housing the filters.

Additionally, sample line/portal 6 permits the gray water to be periodically tested.

In this manner, the entire system permits the laundry water to be collected, filtered, and pressurized for delivery to the irrigation system.

FIG. 2 is a block diagram illustrating the preferred residential embodiment of the gray water treatment system.

Housing 20 contains the entire gray water system. The system receives the untreated gray water via In connector 21A and delivers pressurized and filtered gray water to Out connector 21B.

The incoming gray water is first filtered by filter 22 to remove suspended particles. The filtered gray water is stored in holding tank 23. In this embodiment, for a residential application, holding tank 23 has sufficient capacity to contain a typical week's volume of laundry water from a residence (typically 200 gallons).

Pump 24 is activated by controller 26. Controller 26 activates pump 24 when sensor 26A indicates that gray water is within holding tank 23 and sensor 26B indicates that the water pressure within pressure tank 25 is not within the prescribed range.

The pressurized gray water is communicated to Out Connector 21B from the pressure tank 25.

This embodiment, being contained within a single housing, is easily manufactured and then is simply connected to an existing residential system. This embodiment is also enlarged/expanded to a motel or hotel for a residential unit subdivision having 100-150 units.

FIG. 3 is a block diagram illustrating the gray water treatment system implemented in a hotel setting.

Hotel 30 produces a great volume of gray water from its laundry facility. This gray water is communicated to the gray water treatment system 31 as outlined above and the pressurized gray water is delivered to the irrigation system/timer 32 which delivers the gray water to the landscape 33.

In an alternative embodiment of the invention, the filtered and pressurized gray water is delivered to neighborhood 34, thereby permitting the neighborhood to benefit from the water being generated by hotel 30. In this embodiment, ideally a meter 35 determines the amount of grey water being delivered to the neighborhood either for billing purposes to the neighborhood or to computer any credit which the local water district may provide for recycling grey water.

It is clear that the present invention provides an efficient and cost effective mechanism to conserve water by reusing as much as possible. 

1. A gray water recycling system comprising: a) a filtration mechanism receiving waste water from a laundry facility, said filtration mechanism removing suspended particles from the waste water; b) a holding tank receiving waste water from said filtration mechanism, said holding tank having, 1) a pump for drawing water from said holding tank, and, 2) a float within said holding tank, said float being activated when a water level within said holding tank exceeds a pre-determined level; c) a pressure tank receiving water from said pump, said pressure tank having an activation sensor for activating said pump when pressure within said pressure tank falls below a predetermined level and the float within said holding tank indicates that a water level within said holding tank exceeds a pre-determined level; and, d) an irrigation system receiving water from said pressure tank.
 2. The gray water recycling system according to claim 1, a) further including a housing; and, b) wherein said filtration mechanism, said holding tank, and said pressure tank are contained within said housing.
 3. The gray water recycling system according to claim 1, further including a chemical treatment source communicating treatment chemical to said filtration mechanism.
 4. The gray water recycling system according to claim 3, wherein said filtration mechanism includes a sampling portal for withdrawal of a water sample after flowing through said removable cartridges.
 5. The gray water recycling system according to claim 1, a) wherein said filtration system includes removable filter cartridges; and, b) wherein said waste water is directed to flow through said removable filter cartridges.
 6. The gray water recycling system according to claim 1, further including a timer for periodic activation of said irrigation system.
 7. The gray water recycling system according to claim 1, further including a meter measuring a volume of water flowing to said irrigation system.
 8. The gray water recycling system according to claim 7, wherein said irrigation system is position in a neighborhood.
 9. A gray water recycling system comprising: a) a holding tank receiving waste water from a laundry facility, said holding tank having, 1) a pump for drawing water from said holding tank, and, 2) a float within said holding tank, said float being activated when a water level within said holding tank exceeds a pre-determined level; and, b) a pressure tank receiving water from said pump, said pressure tank having an activation sensor for activating said pump when pressure within said pressure tank falls below a predetermined level and the float within said holding tank indicates that a water level within said holding tank exceeds a pre-determined level.
 10. The gray water recycling system according to claim 9, a) further including a housing; and, b) wherein said holding tank and said pressure tank are contained within said housing.
 11. The gray water recycling system according to claim 10, further including a filtration mechanism receiving waste water from a laundry facility said filtration mechanism removing suspended particles from the waste water prior to delivery of said waste water to said holding tank.
 12. The gray water recycling system according to claim 11, a) wherein said filtration system includes removable filter cartridges; and, b) wherein said waste water is directed to flow through said removable filter cartridges.
 13. The gray water recycling system according to claim 12, wherein said filtration mechanism is contained within said housing.
 14. The gray water recycling system according to claim 9, further including: a) an irrigation system receiving water from said pressure tank; and, b) further including a timer for periodic activation of said irrigation system.
 15. The gray water recycling system according to claim 13, further including a chemical treatment source communicating treatment chemical to said filtration mechanism.
 16. The gray water recycling system according to claim 15, wherein said chemical treatment source is contained within said housing.
 17. A gray water recycling system comprising: a) a holding tank receiving waste water from a laundry facility, said holding tank having, 1) a pump for drawing water from said holding tank, and, 2) a float within said holding tank, said float being activated when a water level within said holding tank exceeds a pre-determined level; and, b) a pressure tank receiving water from said pump, said pressure tank having an activation sensor for activating said pump when pressure within said pressure tank falls below a predetermined level and the float within said holding tank indicates that a water level within said holding tank exceeds a pre-determined level.
 18. The gray water recycling system according to claim 17, further including a filtration mechanism receiving waste water from the laundry facility, said filtration mechanism removing suspended particles from the waste water prior to said waste water being deposited into said holding tank.
 19. The gray water recycling system according to claim 18, a) further including a housing; and, b) wherein said filtration mechanism, said holding tank, and said pressure tank are contained within said housing.
 20. The gray water recycling system according to claim 18, further including a chemical treatment source communicating a treatment chemical to said filtration mechanism.
 21. The gray water recycling system according to claim 20, wherein said filtration mechanism includes a sampling portal for withdrawal of a water sample from said holding tank.
 22. The gray water recycling system according to claim 17, further including an irrigation system receiving water from said pressure tank. 